VARIABLE-FOCAL-DISTANCE LENS SYSTEM AND IMAGING DEVICE

A variable-focal-distance lens system is constituted from, in order from an object side to an image surface side, a first lens unit constituted from a lens having a rotationally symmetrical shape, a second lens unit comprising a first free-form lens in which at least one lens surface is configured as a free-form surface, a third lens unit comprising a second free-form lens in which at least one lens surface thereof is configured as a free-form surface, and a fourth lens unit having an aperture diaphragm and being constituted from a lens having a rotationally symmetrical shape. The second lensunit and the third lens unit are movable in a Y-axis direction, and move in mutually opposite directions. The synthetic refractive power of the second lens unit and the third lens unit is variable, and the fourth lens unit moves in the optical axis direction so as to compensate for fluctuation in the image surface position that accompanies variation in the synthetic refractive power. 本可变焦距透镜系统从物侧到像面侧依次由以下组件构成：第一透镜单元，由具有旋转